Research

Programs

This project aims to determine relevant engineering properties of common geomaterials by simulating the processes that take place on the microscopic scale instead of letting them occur physically as in traditional laboratory experiments.

In Civil Engineering, loads are transferred between structures and the ground principally through contact of surfaces. The nature of the soil-structure interaction can dramatically affect the overall load capacity of a structure and therefore plays a key role in civil engineering design.

Much of Australia's export wealth comes from the export of mined coal. An unavoidable consequence of open-cut mining of coal is that it disturbs large volumes of ground, altering its structure and hydromechanical properties to significant depths.

The aim of this work is to present salinity and hydrological data, for a range of typical spoil materials from the Hunter Valley, that can be used in the modelling and prediction of salt release from overburden piles in abandoned coal mines.

Waste products from industrial operations, if not disposed of properly, have the potential to significantly impact the quality of our natural surface and ground water systems. Geoenvironmental engineering focuses on finding engineered solutions to contaminants that have impacted on groundwater aquifers.

The development of accurate constitutive models for predicting the pre- and post-failure behaviour of geomaterials is of major significance in geomechanics. When implemented in a computational framework such as the finite element method, these models enable engineers to design a wide range of geotechnical
infrastructure such as tunnels, retaining walls, embankments, cuttings, foundations and storage facilities.

Insitu testing of soils has become widespread in recent years due to its cost effectiveness and convenience. Two sophisticated devices for performing insitu tests are the pressuremeter and the dilatometer. Both of these devices are being studied in major research programs using the truck mounted testing
facility NEWSYD.

Many materials depend on interdiffusion in their formation. In service, the components of many materials demix as a result of the high temperatures and large driving forces present, which can lead to a degradation of designed properties.

The collapse of geomaterials can greatly affect the normal working behaviour of geostructures and may even lead to catastrophic failure for a wide range of geostructures such as open-cut pits, underground mines, deep piles, tailings dams, building foundations, offshore rigs and deep wellbores. Collapse
in geomaterials is usually accompanied by various forms of instability such as shear banding, bulging, diffused patterns and cracking.

Diffusion-bonding is a very attractive process for the strong bonding of dissimilar engineering materials in order to form engineering devices and structures. However, because of the differing diffusion rates of the components, porosity often forms in the bonding zone during fabrication or in-service
conditions.

For pavements operating in the inelastic range under repeated load cycles, the shakedown limit is widely accepted as an appropriate design parameter. To predict the shakedown limit for a given pavement with known geometry and material properties, two numerical methods are being developed.

Soft soils are problematic since, under load, they can produce large settlements over a very long time span. These soils are widespread in the coastal region of Eastern Australia, where the population is increasing fast and much infrastructure has to be constructed.Soft soils are problematic since,
under load, they can produce large settlements over a very long time span. These soils are widespread in the coastal region of Eastern Australia, where the population is increasing fast and much infrastructure has to be constructed.

Geotechnical stability analysis is traditionally performed by a variety of approximate methods that are based on the theory of limit equilibrium. Although they are simple and appeal to engineering intuition, these techniques suffer from a number of serious disadvantages, not the least of which is the
need to presuppose an appropriate failure mechanism in advance. This feature can lead to inaccurate predictions of the true failure load, especially for realistic problems involving layered materials, complex loading, or three-dimensional deformation.

Unsaturated soils contain both air and fluid phases in their pores and occur throughout the world. One of their major features is their volume and strength change behaviour upon wetting and drying. The aim of this research is to understand the behaviour of unsaturated soils through laboratory and field
testing, to develop constitutive models that capture their basic features, and to develop robust, efficient algorithms to implement these models and for solving boundary and initial value problems.

Mathematical models have been developed that will accurately predict the long term effectiveness of clay barriers for resisting the dispersion of fluoride contaminated waste. The ultimate objective is to assist practising geotechnical engineers in the design of waste containment systems. The theoretical
work for this project is being complemented by an extensive experimental study of the behaviour of fluoride.